Voyager 2 discovered ten moons when it flew past Uranus in 1986. Nearly 40 years later, James Webb found one it missed: Uranus’s 29th known moon, a tiny world only about 10 kilometres wide hiding among the planet’s inner moons.

Webb's ten long infrared exposures found S/2025 U1 between Ophelia and Bianca, extending a moon census begun by Voyager 2 while exposing how much remains unresolved around Uranus. The post Voyager 2 discovered ten moons when it flew past Uranus in 1986. Nearly 40 years later, James Webb found one it missed: Uranus’s 29th known moon, a tiny world only about 10 kilometres wide hiding among the…